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Condensation problem in the house?
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Pete
Nov 19, 2011, 12:02:44 PM11/19/11
to
About six years ago we refurbished a 134-year old mid-terraced house. It
had never had any form of central heating so we installed a full gas
central heating system and a gas fire in each of the two downstairs
rooms, the only other room downstairs being the kitchen which has a
small radiator and the boiler is wall-mounted in there too. There is
loft insulation but as there are no wall cavities, there is obviously no
cavity wall insulation.
uPVC double glazed windows and doors were fitted in the refurb as well.
When the work was finished we wanted to rent out the house but didn't
want to be involved with it so we do it through a lettings agency. The
first tenants were in there for about 4.5 years and the current tenants
have been there since the first ones left.
The agency contacted us recently to say that the tenant has been
complaining of a damp problem in the downstairs rooms, with some of her
belongings and the settee and cushions becoming mouldy, and they offered
to send in a specialist damp company to investigate but not to do any
remedial work until we give the go-ahead.
I got a text from the tenant today saying that the specialists advised
getting in one or more dehumidifiers, and was I going to do this and
when? I've not been notified of anything by the agency yet so I said
that I'd talk to them on Monday and get back to the tenant after that.
Now, I'm no expert by any means but their suggestion of dehumidifiers
would suggest to me that they think it's a condensation problem. My
first question has got to be, why now? After six years since the house
was completely refurbed, what has changed for this problem to begin now?
I've only seen the tenants and/or been to the house very rarely since
they moved in but on those rare ocassions that I have, I get the
impression that they may be eco/green types who would rather put on
about half a dozen jumpers and sit watching telly wrapped up in a
blanket rather than put the heating on - could this be anything to do
with it, if they don't indeed have the heating on much?
Second question is, how to tackle the problem permanently as I'm
thinking that dehumidifiers are a temporary solution?
TIA
Bob Minchin
Nov 19, 2011, 12:52:38 PM11/19/11
to
from time to time and dries washing on radiators,boils veg on the stove
with out running the kitchen extractor, runs baths by putting in the hot
water first rather than mixing with cold etc.
Often difficult to persuade the tenant that they are the cause of the
problem though.
Bob
NT
Nov 19, 2011, 12:56:04 PM11/19/11
to
going on. I'd have said no to damp specialists, most are no more than
scammers, but it sounds like you've gotten away without the usual bs.
You cant really force the tenants to heat the house more, and a
dehumidifier is fine as a long term solution.
ps a fair few victorian houses have cavity walls, yet its widely
believed that none do, even by people in various areas of the building
trade.
NT
Allan Mac
Nov 19, 2011, 2:02:17 PM11/19/11
to
Hi
pardon my ignorance if I'm off the mark but do gas fires themselves
not produce a lot of water vapour?
Allan
pardon my ignorance if I'm off the mark but do gas fires themselves
not produce a lot of water vapour?
Allan
Steve Walker
Nov 19, 2011, 2:34:06 PM11/19/11
to
chimney. Flueless ones are a problem.
SteveW
Fredxx
Nov 19, 2011, 2:41:09 PM11/19/11
to
humidistat, and a true extract in the kitchen. Without those it doesn't
surprise me in an otherwise well "sealed" house.
Lobster
Nov 19, 2011, 7:24:04 PM11/19/11
to
On 19/11/2011 17:52, Bob Minchin wrote:
> Pete wrote:
> Pete wrote:
>> I got a text from the tenant today saying that the specialists advised
>> getting in one or more dehumidifiers, and was I going to do this and
>> when? I've not been notified of anything by the agency yet so I said
>> that I'd talk to them on Monday and get back to the tenant after that.
>>
>> Now, I'm no expert by any means but their suggestion of dehumidifiers
>> would suggest to me that they think it's a condensation problem. My
>> first question has got to be, why now? After six years since the house
>> was completely refurbed, what has changed for this problem to begin now?
>> getting in one or more dehumidifiers, and was I going to do this and
>> when? I've not been notified of anything by the agency yet so I said
>> that I'd talk to them on Monday and get back to the tenant after that.
>>
>> Now, I'm no expert by any means but their suggestion of dehumidifiers
>> would suggest to me that they think it's a condensation problem. My
>> first question has got to be, why now? After six years since the house
>> was completely refurbed, what has changed for this problem to begin now?
> It's usually a lifestyle thing. If the tenant does not open the windows
> from time to time and dries washing on radiators,boils veg on the stove
> with out running the kitchen extractor, runs baths by putting in the hot
> water first rather than mixing with cold etc.
>
> Often difficult to persuade the tenant that they are the cause of the
> problem though.
I agree totally with Bob on both counts.
> from time to time and dries washing on radiators,boils veg on the stove
> with out running the kitchen extractor, runs baths by putting in the hot
> water first rather than mixing with cold etc.
>
> Often difficult to persuade the tenant that they are the cause of the
> problem though.
I seem to have solved it myself in a rented-out two-up-two-down by
fitting the bathroom with a humidistat-controlled extractor fan and
advising the tenants to keep the bathroom door open so that it has a
chance to work over the whole property - seems to have done the trick.
Other than that, providing a dehumidifier seems a reasonable
propositition, except that if they are eco-warriors as you say, they'll
probably baulk at switching the thing on... :(
David
harry
Nov 20, 2011, 2:51:07 AM11/20/11
to
On Nov 19, 5:52 pm, Bob Minchin
> Bob- Hide quoted text -
>
> - Show quoted text -
+1
Also uses the shower a lot.
>
> - Show quoted text -
+1
Also uses the shower a lot.
Allan Mac
Nov 20, 2011, 4:03:05 AM11/20/11
to
On Nov 19, 7:34 pm, Steve Walker <st...@remove-this.walker-
yes off course I was thinking of those portable heater things.
Kipper at sea
Nov 20, 2011, 4:23:12 AM11/20/11
to
On Nov 19, 5:02 pm, Pete <n...@wanted.com> wrote:
cause condensation, from bath, shower and cooking. The answer is
extractors in the kitchen and bathroom with a window open while
cooking and after showering or bath. Portable gas fires are one of the
biggest condensation makers.
js.b1
Nov 20, 2011, 6:13:12 AM11/20/11
to
Flat out lack of ventilation...
Dehumidifiers are one solution.
- They are expensive to run, 250W (compressor) to even 800W
(dessicant)
- They are not cheap to buy £130 for a DD8L to £320 for Mitsubishi
- You really need two re hall & main living area
- They are barstool noisy if you want to run at night
Better solution is a programmed ventilation.
- Airflow Quietair QT100T
- Cheap to run at 10Watt, 6 min every 24hr to 23min every 4hrs
- Cheap to buy at £65
- Awkward to fit re dust creation needing dust sheets taped to wall
I have not used that exact model, and there are other similar products
available, but the idea is sound - you create enforced ventilation to
keep humidity below about 68% which is when mould begins to get
excited.
Do the open flue(s) have a rain cap? You get about 72" of rainfall or
something silly down an open flue annually. Quite a few gas fires when
not in use can provide limited ventilation depending on the cold draw
of the chimney, so moisture can build up. Put on the other gas fire
and it will draw air down the other chimney often bringing mould laden
air with it.
A puzzle is how can the baseline level of ventilation be low yet you
have two gas fires - unless they are balanced flue? Balanced flue draw
in their own air for combustion via the inset tube, exhausting
products of combustion through the outer tube. A seriously defective
fitment can result in leakage into the room or cavity but this is
solid wall.
Has the occupier bunged up every vent?
If the problem is draughts the "Black Hole" labyrinth ducted things
supposedly work. They tend to require a 125mm core drill, most
enforced extractors use a 107mm core drill. 780W drill is usually
sufficient unless you have pig hard bricks in which case hire - and
also hire a very good dust cleaner because core drills produce "brick
flour" on an epic scale.
I think heat recovery fans of the "1-piece in a wall" will be a
disaster outside a lab because if there is any reduction in flow from
back pressure or prevailing wind the actual heat recovered will
plummet. Extracting heated air is not really a problem - in moderation
- because it is the fabric which takes time to heat, it takes very
little to reheat the amount of air removed. Just a case of dishonest
lobbyists and garbage research. The central heat recovery units will
work ok - if adequately lined - although their price seems somewhat
ridiculous as with most "Govmint says you must have and we collect the
lolly".
Dehumidifiers are one solution.
- They are expensive to run, 250W (compressor) to even 800W
(dessicant)
- They are not cheap to buy £130 for a DD8L to £320 for Mitsubishi
- You really need two re hall & main living area
- They are barstool noisy if you want to run at night
Better solution is a programmed ventilation.
- Airflow Quietair QT100T
- Cheap to run at 10Watt, 6 min every 24hr to 23min every 4hrs
- Cheap to buy at £65
- Awkward to fit re dust creation needing dust sheets taped to wall
I have not used that exact model, and there are other similar products
available, but the idea is sound - you create enforced ventilation to
keep humidity below about 68% which is when mould begins to get
excited.
Do the open flue(s) have a rain cap? You get about 72" of rainfall or
something silly down an open flue annually. Quite a few gas fires when
not in use can provide limited ventilation depending on the cold draw
of the chimney, so moisture can build up. Put on the other gas fire
and it will draw air down the other chimney often bringing mould laden
air with it.
A puzzle is how can the baseline level of ventilation be low yet you
have two gas fires - unless they are balanced flue? Balanced flue draw
in their own air for combustion via the inset tube, exhausting
products of combustion through the outer tube. A seriously defective
fitment can result in leakage into the room or cavity but this is
solid wall.
Has the occupier bunged up every vent?
If the problem is draughts the "Black Hole" labyrinth ducted things
supposedly work. They tend to require a 125mm core drill, most
enforced extractors use a 107mm core drill. 780W drill is usually
sufficient unless you have pig hard bricks in which case hire - and
also hire a very good dust cleaner because core drills produce "brick
flour" on an epic scale.
I think heat recovery fans of the "1-piece in a wall" will be a
disaster outside a lab because if there is any reduction in flow from
back pressure or prevailing wind the actual heat recovered will
plummet. Extracting heated air is not really a problem - in moderation
- because it is the fabric which takes time to heat, it takes very
little to reheat the amount of air removed. Just a case of dishonest
lobbyists and garbage research. The central heat recovery units will
work ok - if adequately lined - although their price seems somewhat
ridiculous as with most "Govmint says you must have and we collect the
lolly".
Hugo Nebula
Nov 20, 2011, 7:40:41 AM11/20/11
to
[Default] On Sat, 19 Nov 2011 19:34:06 +0000, a certain chimpanzee,
Steve Walker <st...@remove-this.walker-family.me.uk>, randomly hit the
flueless ones. Have the tenants been experiencing headaches?
--
Hugo Nebula
"If no-one on the internet wants a piece of this,
just how far from the pack have I strayed"?
Steve Walker <st...@remove-this.walker-family.me.uk>, randomly hit the
keyboard and wrote:
>On 19/11/2011 19:02, Allan Mac wrote:
>> pardon my ignorance if I'm off the mark but do gas fires themselves
>> not produce a lot of water vapour?
>On 19/11/2011 19:02, Allan Mac wrote:
>> pardon my ignorance if I'm off the mark but do gas fires themselves
>> not produce a lot of water vapour?
>The water vapour from most gas fires doesn't matter, as it goes up the
>chimney. Flueless ones are a problem.
Check that the chimney is clear. It could be that they are acting as
>chimney. Flueless ones are a problem.
flueless ones. Have the tenants been experiencing headaches?
--
Hugo Nebula
"If no-one on the internet wants a piece of this,
just how far from the pack have I strayed"?
Hugo Nebula
Nov 20, 2011, 7:55:33 AM11/20/11
to
[Default] On Sat, 19 Nov 2011 17:02:44 -0000, a certain chimpanzee,
Pete <n...@wanted.com>, randomly hit the keyboard and wrote:
>About six years ago we refurbished a 134-year old mid-terraced house. <...>
If it's an older property, I suspect the walls are solid masonry. They
act like 'storage heaters' and respond better to permanent low levels
of heating rather than short bursts. Old properties can take several
days to heat up.
If the tenants are reluctant to turn the central heating on, they may
be relying on the gas fires for a few hours which only manages to heat
up the air in the room and a few millimetres of the wall causing the
dew point to appear in the plaster!
If you've got a functioning central heating system, then take the
fires out. Stick a programmable roomstat in with a minimum setting of,
say, 16-degrees. If they must have a fire in the living room, try a
solid fuel one. It's easy to sell it on ecological grounds - it uses
timber which only releases the carbon already captured. That, and the
flue would ventilate the room.
Pete <n...@wanted.com>, randomly hit the keyboard and wrote:
>About six years ago we refurbished a 134-year old mid-terraced house. <...>
If it's an older property, I suspect the walls are solid masonry. They
act like 'storage heaters' and respond better to permanent low levels
of heating rather than short bursts. Old properties can take several
days to heat up.
If the tenants are reluctant to turn the central heating on, they may
be relying on the gas fires for a few hours which only manages to heat
up the air in the room and a few millimetres of the wall causing the
dew point to appear in the plaster!
If you've got a functioning central heating system, then take the
fires out. Stick a programmable roomstat in with a minimum setting of,
say, 16-degrees. If they must have a fire in the living room, try a
solid fuel one. It's easy to sell it on ecological grounds - it uses
timber which only releases the carbon already captured. That, and the
flue would ventilate the room.
Pete
Nov 20, 2011, 8:06:03 AM11/20/11
to
In article <MPG.2931f18b...@news.btinternet.com>,
n...@wanted.com says...
Sorry about the delay in getting back to you, had to go visit the in-
laws after a bit of an emergency although all is now well. Thanks for
all the suggestions - I'm afraid we've got to go out again now so I
haven't time to reply to each one or really take it all in yet but I
really do appreciate the help and we'll go over everything later. Cheers
all.
n...@wanted.com says...
laws after a bit of an emergency although all is now well. Thanks for
all the suggestions - I'm afraid we've got to go out again now so I
haven't time to reply to each one or really take it all in yet but I
really do appreciate the help and we'll go over everything later. Cheers
all.
NT
Nov 20, 2011, 1:42:30 PM11/20/11
to
On Nov 20, 11:13 am, "js.b1" <js...@ntlworld.com> wrote:
> Flat out lack of ventilation...
>
> Dehumidifiers are one solution.
> - They are expensive to run, 250W (compressor) to even 800W
> (dessicant)
> - They are not cheap to buy £130 for a DD8L to £320 for Mitsubishi
> - You really need two re hall & main living area
> - They are barstool noisy if you want to run at night
>
> Better solution is a programmed ventilation.
> - Airflow Quietair QT100T
> - Cheap to run at 10Watt, 6 min every 24hr to 23min every 4hrs
> - Cheap to buy at £65
> - Awkward to fit re dust creation needing dust sheets taped to wall
We did the calcs comparing the 2 options here a while back, and found
> Flat out lack of ventilation...
>
> Dehumidifiers are one solution.
> - They are expensive to run, 250W (compressor) to even 800W
> (dessicant)
> - They are not cheap to buy £130 for a DD8L to £320 for Mitsubishi
> - You really need two re hall & main living area
> - They are barstool noisy if you want to run at night
>
> Better solution is a programmed ventilation.
> - Airflow Quietair QT100T
> - Cheap to run at 10Watt, 6 min every 24hr to 23min every 4hrs
> - Cheap to buy at £65
> - Awkward to fit re dust creation needing dust sheets taped to wall
the dh option to be significantly cheaper overall. Dont forget the dh
only runs a fraction of the time, doesnt chuck heat outdoors, and is a
lot more effective at dropping rh.
NT
ARWadsworth
Nov 20, 2011, 3:55:51 PM11/20/11
to
--
Adam
* Sometimes I like to lay in my neighbours garden and pretend to be a
carrot *
js.b1
Nov 20, 2011, 4:50:04 PM11/20/11
to
On Nov 20, 6:42 pm, NT <meow2...@care2.com> wrote:
> We did the calcs comparing the 2 options here a while back, and found
> the dh option to be significantly cheaper overall. Dont forget the dh
> only runs a fraction of the time, doesnt chuck heat outdoors, and is a
> lot more effective at dropping rh.
Interesting...
> We did the calcs comparing the 2 options here a while back, and found
> the dh option to be significantly cheaper overall. Dont forget the dh
> only runs a fraction of the time, doesnt chuck heat outdoors, and is a
> lot more effective at dropping rh.
For handling humidity in a bedroom for a relative I am fitting a
Xpelair DX100PC (manual pullcord) to see how it performs.
For a different reason (water damage to a shed/store) I have a DD8L on
the way, so I may give it a try to see how it goes. As a dessicant
dehumidifier it acts as a fan heater which merely displaces an
electric wall heater. The unknown is noise & jet blast, the minimum
330W setting should be ok.
The problem with dehumidifiers is they do not dehumidify an entire
house unless you take all the doors off, so you end up having to move
them room to room. About as exciting as vacuuming (I am the only
person to wear a Miele out, and it takes some doing).
NT
Nov 21, 2011, 3:52:02 AM11/21/11
to
On Nov 20, 9:50 pm, "js.b1" <js...@ntlworld.com> wrote:
> On Nov 20, 6:42 pm, NT <meow2...@care2.com> wrote:
> > We did the calcs comparing the 2 options here a while back, and found
> > the dh option to be significantly cheaper overall. Dont forget the dh
> > only runs a fraction of the time, doesnt chuck heat outdoors, and is a
> > lot more effective at dropping rh.
>
> Interesting...
>
> For handling humidity in a bedroom for a relative I am fitting a
> Xpelair DX100PC (manual pullcord) to see how it performs.
>
> For a different reason (water damage to a shed/store) I have a DD8L on
> the way, so I may give it a try to see how it goes. As a dessicant
> dehumidifier it acts as a fan heater which merely displaces an
> electric wall heater. The unknown is noise & jet blast, the minimum
> 330W setting should be ok.
200w domestic refrigeration types arent normally a noise issue. Larger
> On Nov 20, 6:42 pm, NT <meow2...@care2.com> wrote:
> > We did the calcs comparing the 2 options here a while back, and found
> > the dh option to be significantly cheaper overall. Dont forget the dh
> > only runs a fraction of the time, doesnt chuck heat outdoors, and is a
> > lot more effective at dropping rh.
>
> Interesting...
>
> For handling humidity in a bedroom for a relative I am fitting a
> Xpelair DX100PC (manual pullcord) to see how it performs.
>
> For a different reason (water damage to a shed/store) I have a DD8L on
> the way, so I may give it a try to see how it goes. As a dessicant
> dehumidifier it acts as a fan heater which merely displaces an
> electric wall heater. The unknown is noise & jet blast, the minimum
> 330W setting should be ok.
ones are another matter, but 200w is enough for most jobs.
> The problem with dehumidifiers is they do not dehumidify an entire
> house unless you take all the doors off, so you end up having to move
> them room to room.
kitchen etc, putting the dh there is quite effective.
> About as exciting as vacuuming (I am the only
> person to wear a Miele out, and it takes some doing).
NT
Nov 21, 2011, 3:58:53 AM11/21/11
to
On Nov 20, 8:55 pm, "ARWadsworth" <adamwadswo...@blueyonder.co.uk>
wrote:
Regrettably I didnt find it. I'd redo them if I could remember the
real life run times of the fan in a situation where I've used both,
but I cant.
NT
wrote:
real life run times of the fan in a situation where I've used both,
but I cant.
NT
MuddyMike
Nov 21, 2011, 4:07:44 AM11/21/11
to
"harry" <harol...@aol.com> wrote in message
news:d5046384-eee0-4e4d...@gi1g2000vbb.googlegroups.com...
Also ask how they dry laundry.
Mike
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